1. Field
The present invention relates to an electric contact electrically connected to an electrical part such as a semiconductor device (hereinafter referred to as “IC package”), and a socket for electrical part in which this electric contact is disposed.
2. Description of Related Art
Conventionally, probe pins arranged in an IC socket for use as a socket for electrical part have been known as this type of electric contacts. This IC socket is disposed on a wiring board and configured to house an IC package, which is an inspection object. Terminals of this IC package are electrically connected to electrodes of the wiring board through the probe pins.
The probe pins have a structure in which a foundation layer and a surface layer are formed on a base material. On the other hand, some of the terminals of the IC package include a layer of so-called lead-free solder (i.e., solder composed primarily of tin and not containing lead) formed on surfaces of each terminal. In a continuity test or the like of the IC package, the surface layer of each probe pin and the lead-free solder layer of each IC package terminal are electrically connected to each other as the result of being brought into contact with each other (see, for example, Domestic Re-publication No. 2007/034921).